A Black Heart
by ForbiddenKHfan216
Summary: An alternate universe, where Xion is left the survivor of the procedure used to bring Sora back to life. With the knowledge of having destroyed some of her most precious people, she is drawn into insanity. Her only friend? Roxas's voice, trapped within her mind... With his guidance, Xion will destroy the Organization. Once there were 13, now 1 by 1, they will all fall.
1. Chapter one: Sonata of Madness

**Alright, I have to give credits for this one. This is one of my first co-writing (Katy, it never made it onto the site so the Power Rangers thing doesn't count) and we must all welcome my buddy, who stole Riku's name... Riku Takamura the writer!**

***claps***

**This was all his idea, but since I have mad writing skills (Since when exactly? Ha!) I was picked to write it. Therefore, all nutballness is on my part, not Emo Boy. I have no idea where we're going with this, so just enjoy the show! **

**Disclaimers: Kingdom Hearts, Final Fantasy and Disney do not belong to either of us. The story-line is a combination of efforts, so it belongs to us. Any original characters will be trademarked by either ForbiddenKHFan216 or Riku Takamura. Read and review people!**

**If you would like to comment, go to either of our profiles and give us a PM. If you want to yell at someone, yell at Riku! I don't do well under stress. It makes me break out five pound chocolate bars and cry out that I'm never going to be happy again.**

**Disclaimer 2: that reference belongs to A Very Potter Musical. I do apologize.**

* * *

Chapter One: Sonata of Madness

At the sound of his voice, the girl turns around, obviously startled. Axel looks at her, holding his hand out to her in a begging gesture. "Come home. Please." He says softly, taking a step forward. The moment he moves, however, Xion takes a step back, her dark eyes narrowing in distrust. She turns away from him again, her deep hood hiding the anger in her expression.

At first, her voice is so low, not even she could hear it. Axel takes another step forward, and another, until he could reach out and place his hand on her shoulder. She stiffens in his embrace, but repeats what she said. "I don't have a home, Axel. I never did." At her harsh words, Axel scowls, his mouth opening to protest. Xion continues quietly. "If I had one... my home was with you and Roxas. And I destroyed that. Thanks to the _**Organization**_." She sneers that final word, surprising Axel with the intensity of her venom. She clutches her hand tightly into a fist, beginning to shake with the sheer force of her emotions.

Axel squeezes her shoulder gently, wrapping his other arm around the younger girl's waist. She looks up at him, and for a moment, it almost seems like she was about to collapse into him and cry. Instead, she pulls away and pulls her hood back over her eyes. She shakes her head no and begins to walk further into the dark streets of the City. He grabs her hand, forcing the girl into a stop.

"Don't." She says softly, pulling away from him.

He bows his head, his fingers curling into a fist. A furious grimace briefly takes place on his features before turning blank, the emotions quickly fading from his Nobody body. "And why should I? The Organization needs you. We lost one Keyblade wielder. We need you, Xion. … I need you, XIV. We're friends... aren't we?"

This last sentence is delivered weakly, as if Axel wanted desperately for it to be true.

Xion's eyes narrow darkly beneath her hood, a demented smile slowly stretching across her lips. "You... _need_ me, Axel? The _Organization_ needs me?" She repeats softly, a low laugh coming from deep within her. Unable to help, Axel suddenly shivers at the cruel, cold noise, staring at her in sheer disbelief. There was no way... that his little girl and best friend could... or would... be able to make that laugh!

With one gloved hand, Xion throws off the hood, turning around to face her former best friend. "Don't make me laugh. That's not what you want at all." She says calmly, grimacing at him.

Long, almost melted-looking scars decorated the side of her face now, remnants of what Axel could guess was her battle for supremacy within her own body. She had battled hard to gain control... and these scars were her price for it. Noticing her friend's disgusted expression, Xion slowly traces down her now useless right eye, which was completely swollen shut from the sheer mass of scar tissue around it. Her gloved finger almost lovingly touches the blackened scars, bouncing along the pits and gashes that had bubbled on the surface of her skin.

She looks like she had been dipped in acid... and forced out just before she died. One side of her face is almost the same, if only a little sadder than it had ever been. The other is almost completely warped from the sheer amount of scars. Some look like chemical burns, others like she had been stabbed with some sharp object until it pierced into her very muscles. Because of this, and because of the demented smile on that part of her face, Axel knows that she had in fact suffered damage in her face, something below the surface that couldn't be fixed.

"Well, Axel...? Do you think you still need me?" Xion asks curiously, her single eye sparkling with some hidden maliciousness that the older Nobody had no idea that she possessed. She steps forward, and for the first time, Axel notices that her hands swing uselessly by her sides. She notices the look and her smile deepens. "It's worse on my hands. And on my body. My chest is especially bad. Roxas... didn't want to go peacefully. He didn't accept it." Without warning, Axel suddenly feels the younger girl grip his shoulders tightly. He looks down at her and a shiver goes down his spine at the enraged expression in her gaze.

She continues softly, almost like she was talking to herself. "He didn't accept me... She didn't accept that I wanted to live," Axel stares at her, watching as her face contorts into a savage expression, like she wanted to tear him apart and kill him slowly. As if following this impression, Xion's hands wrap around Axel's throat, beginning to crush the man's windpipe slowly. He gasps for breath but she continues to speak. "I didn't want to die, Axel. I didn't. But it's okay now. We're going to be together forever... best friends _forever_... remember?" A high-pitched giggle comes out of her lips and Xion's smile widens.

Axel collapses to his knees, struggling to get the girl's hands off of him. He scrambles at her gloves, hearing … things... burst inside of it, but he was still unable to get her off. Her head comes close to his, her lips to his ear. "You _promised_... we'd go to the beach... Axel..." She whispers hoarsely, giggling softly to herself.

Axel recognizes that voice. And he knows exactly what had happened.

_Roxas_... had done this.

He whispers his best friend's name before sliding his hands around the younger girl's stomach and onto her lower back, closing his eyes with regret. "I'm sorry... Xion... Roxas..." He says quietly, holding her body close to his for a single moment, as if he would never let her go.

The moment that the flames begin to crawl up the girl's black clothing, she lets out a horrified scream, a scream that would remain trapped within the older Nobody's mind for the rest of his miserable existence. It was the scream of two people, trapped within one body but only having a single mouth to let out their rage and fear. Both the slightly deeper voice of Roxas and Xion's own high-pitched shriek combine together, their varying emotions tangling themselves into a single loud noise.

Axel only squeezes his eyes even tighter, throwing all of his body weight into his hands to throw Xion off of him, saving his own life.

Xion tumbles backward, flailing her arms in a contorted pinwheel that in some other time, some other place, might have actually been somewhat comical. The moment that Xion hits the ground, however, her head slams into the cobblestone street, cutting off her loud shriek as abruptly as if someone had suddenly flipped off the sound switch inside of her. Instead, she simply lies there on the floor, her dark blue eyes bulging out of their sockets as the flames suddenly sputter out.

Axel coughs violently, wheezing as he somehow manages to get to his feet, pushing himself upward with a weak arm. He rubs his throat, wincing as the dark bruise that the young girl's fingers had made throbs in between his own. Already, it was beginning to ache badly; she had put an extraordinarily large amount of force into the attack, one that he would have sworn that she didn't have.

Either way, it wouldn't matter anymore.

Axel holds his hand out to the side, sighing softly as a series of black, flame-like tendrils begins to crawl up his damaged arm. "Don't worry... it'll be over soon..." He says quietly to the still body before him, tilting his head back to look at the stunned child. Her eyes flicker towards him as he moves forward, as he moves towards her.

The sharp edges of the Eternal Flame chakrams gleam ominously as the man dubbed the "Flurry of Dancing Flames" suddenly smiles. In his long thin fingers, the chakrams look less like a bizarre set of Frisbees and more like a deadly weapon. Xion hisses slightly, beginning to recover herself in the rapid way that most Keyblade wielders did. Axel lightly presses his boot-clad foot into her chest just as she starts to sit up, no doubt to attack him again with the Keyblade that had appeared in her little hand.

Strange things, Keyblades. They didn't seem to give a rat's ass about disobeying (and breaking, Axel thought humorlessly) every rule of physics and science that ever existed as long as they could protect their masters. This gave the Wielders that much more power, and that much more strength.

It also made them that much more weak.

Axel lightly kicks the golden Key out of the girl's hand, knowing she was almost powerless without it. It spins away from them both, clattering loudly against one of the walls of the Dark City. The metallic noise echoes slightly in the dark alleyway, allowing the girl one moment to shriek in anger and to spit in Axel's general direction. He dodges the missile, and just looks at the broken shell of his friend in a detached sort of mourning.

He bows his head, keeping his foot firmly placed on her chest. With a funny sort of grim feeling, he figures out slowly that she was so angry because she had no magic left at all. He glances at the almost healed scar on her face, the one that curved so violently around her eye and down her cheek. Just how much magic had been used to keep her from having half of her face torn and burned off? A lot, he assumes.

He kneels onto her body and lightly places his hand onto her cheek, sighing softly as he gives her one last mercy. Axel, the infamous assassin of Organization XIII, curls his hand around her cheek, gently holding her for one last moment. "I loved you a lot, Xion. You too, Roxas," He says quietly, unknowingly smiling kindly at the young girl beneath him. She stares at him, a bewildered look in her one open eye. He just chuckles softly, closing his eyes regretfully. "I loved you. I don't want you to live like this, no way. … Best friends forever, Xion. I'll be there soon." He tells her as the hand wielding the bladed weapon suddenly raised slightly.

As a single tear drips down the Nobody's cheek, sliding down and dropping onto Xion's own cheek, the young girl's eye suddenly clears of the insane rage. She lets out a soft breath, her face contorting into a miserable sort of smile. "A...xel..." She whispers quietly, laughing to herself as the blade comes down.

Even as her jugular is slit and torn open, Xion doesn't stop smiling.

Axel gets up, wiping the bladed weapon unceremoniously on his jacket. He raises a hand to his cheek. He smirks slightly. "I didn't know I could still cry." He says finally to the small corpse in the alleyway, only pausing to lift the hood over her face before he snaps his long fingers together. Without another word, he walks into the Corridor of Darkness, vanishing within the tendrils of its dark energy without another glance back at his former friend.

He knew he would end up bawling like an infant if he had.

Either way, time to RTC.


	2. Chapter Two: Requiem for a Nobody

**Chapter Two: Requiem for a Nobody**

He stares down at the body with distaste, his hidden eyes narrowing as he looks at the girl. Once, he would have run to her side before that other Nobody even dared touch her... but now...? A cold smile slowly spreads across his face as he kneels down beside the body, lightly lifting the tiny girl up into his arms.

Well, now he was damn happy she was dead.

He glances at the body as he very gently slips his arms underneath her legs, slowly standing up. As he moves, Xion's corpse slowly settles into his chest and he smiles again, though bitterly this time. A few days ago, he might have enjoyed holding the girl like this.

Today, Riku was just the clean-up crew.

He stands up all the way, clutching the rag doll-like girl to his own body. Almost without noticing, he gently pulls the girl's jacket over her head, protecting her face from the harsh wind of the Dark City streets. As he adjusts the cloak, he hears an audible breath coming from her bloodied lips. Now that was another complication.

But he could work with this one.

* * *

As usual, the little girl doesn't move as he enters the room, not even when he slams the door behind him so hard that it rattles the windows of the dank prison cell.

He knows he should be used to it, but really, all it did was make him that much more angry. She should have been awake, she should have been talking to him. He wants her to be able to speak to him already, he needs to know the information buried deep within that head in order to understand what he had to do. The boy looks at the girl from beneath the black blindfold he wore, once more feeling that urge in his hand to wrap his fingers around her throat and choke the life right out of her. It would be easy.

It would be so very easy.

A hand claps onto his shoulder, immediately startling him out of his grim thoughts. DiZ smiles at him from deep within the folds of the contraption of red cloth that covered his face. "Now then, Ansem. Do be calm." He says quietly, patting the boy's shoulder fondly. The boy flinches and looks away, but continues to gaze at the girl from the corner of his eye.

DiZ chuckles. The fascination, even if it was only from the rage that the boy had for her, is amusing to the old man. It reminds him of other, more happy dreams. "Ansem. Check on Naminé. It seems she still hasn't eaten. … Just like you have not."

The boy glares at him from under the blindfold but nods. "Yes... It still doesn't seem real." He murmurs in a strange voice, a voice that was much too deep for a boy like him. It sounded like a grown man's voice, rather than the sixteen year old boy standing before him.

DiZ nods in agreement. The boy continues to speak softly, more to himself than anyone else. "All my memories are back... and it feels even worse because of that. Because I know who Sora is again. … Because I know he can't keep his promise now." He sighs, trembling slightly with grief. For a moment, he feels the tears trickle into his blindfold and – not for the first time, either – and he is grateful for the strip of cloth hiding his eyes. It meant that DiZ couldn't see him cry. "Kairi... won't be able to see him again... I... can't take care of her..." The last words are muttered like a curse and the boy trembles that much harder.

He seems more concerned about this promise than going back to see the girl who was mourning his friend.

DiZ turns his gaze onto the sleeping child, her face hidden within the folds of her own cloak, thankfully. Her scars are grotesque, even for someone who had treated his own student when he lost his eye. There was no comparison to what had happened to this girl. She had been tortured, or so it appeared. The memories of one who refused to die are a powerful force, apparently, as the unnamed Nobody had struggled for dominance within the sleeping child's form. He has a theory about that. Perhaps, due to how powerful the second Nobody had been, he hadn't been content to go quietly. Perhaps he had decided to wreck the form he was now forced to share, destroying parts of it and crippling others. It also seemed like a punishment. To punish her for choosing Sora over him, perhaps? Had this unknown Nobody known about Sora and what Xion had been hoping to accomplish? DiZ wasn't sure and not exactly sure that he wanted to ask her when she woke up.

DiZ, despite whatever pity he had for the once Nobody girl, claps his hand back onto Riku's shoulder. The boy looks up, startled. "Go home. Take Naminé with you, perhaps. … I'm sure your friend would want to see you, especially with this news." He says softly, feeling a tinge of sympathy for once. Riku, the boy disguised as Ansem, pauses for a moment before nodding.

"Yeah. Sure." Riku says, his voice shifting from the deep baritone of Ansem to his own. DiZ smiles at him and the boy takes that as his cue to leave. He turns around and heads for the door, quietly shutting behind him. As he walks down the hall, his fingers twitch slightly. He curls his hands into fists, reluctantly hiding the desire to strangle the sleeping girl... for now.

*K*H*D*X*

It's dark.

The thing's eyes flicker slightly and they open, close, close, open...

_'Where am I?'_

It didn't know.

_'Who are you?'_

It didn't know.

_'This is stupid.'_

Did it even matter?

The thing's eyes keep opening and closing as it stares at the electric light hanging from the ceiling above it. For whatever reason, its dark blue eyes remain fixated on it even though it burns them and makes them ache with pain. The light is bright and harsh, washing away any shadows that could have been in the room into nothingness and more light.

White. It knew white.

A smile crosses the child's face and it laughs softly to itself in the darkness. No, it didn't just know white. She, Xion of Organization XIII, the Mysterious Number, also knew the color red.

She remembers the color red, and she remembers exactly how to retrieve it from the veins of her enemies.


End file.
